Sequential methotrexate and 5-fluorouracil therapy for gastric cancer patients with peritoneal dissemination: a retrospective study

Background. Most gastric cancer patients with peritoneal dissemination have been excluded from clinical studies because they usually have no measurable lesions. They also have a high risk of toxicity because of complications such as intestinal obstruction and ascites. We conducted a retrospective analysis to evaluate the efficacy and feasibility of sequential methotrexate (MTX) and 5-flurorouracil (5FU) therapy for this population. Methods. This analysis was based on 56 consecutive chemotherapy-naive patients with confirmed peritoneal dissemination of gastric cancer who were being treated with sequential MTX/5FU. The therapy comprised a weekly schedule of MTX 100 mg/m², given as a bolus infusion 3 h prior to a bolus infusion of 5FU 600 mg/m². Leucovorin 10 mg/m² was administered six times, every 6 h, starting 24 h after MTX administration. Results. Evidence of peritoneal dissemination was confirmed by laparotomy in 16 patients, by cytologic examination of ascites in 11 patients, and by clinical imaging in 29 patients (15 with ascites, 13 with intestinal obstruction; in 10 of the 29 patients, detection was by barium enema or computed tomography [CT] scan). Neutropenia of grade 3 or worse and anemia were observed in 8 (14%) and 10 (18%) of the 56 patients, respectively. There was one treatment-related death due to neutropenic sepsis. Of the 26 patients with measurable lesions, 9 showed a response (36%). The median survival time and median time to treatment failure were 259 days and 167 days, respectively. Objective improvement of ascites was seen in 13 of 26 patients (50%), including 5 with showed complete disappearance of ascites. Seven of the 15 patients (47%) with intestinal obstruction showed resolution, and 8 of the 21 patients (38%) who needed nutritional support before the treatment were free of that support for a median duration of 220 days after the completion of the treatment. Forty-seven of the 56 patients (84%) could be treated at outpatient clinics. Conclusions. This regimen may be of clinical benefit for patients with peritoneal dissemination of gastric cancer. Received: August 24, 2001 / Accepted: October 19, 2001